The Pythagorean Theorem tells us that a 3-4-5 triangle is a right triangle, so we can simply test for sides of 3, 4, and 5.

勾股定理(Pythagorean Theorem)告诉我们边长为3、4和5的三角形是直角三角形，因此可以使用边长3、4和5来简单地测试。

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In 1820, German mathematician Karl Friedrich Gauss proposed cutting an enormous right triangle into the Siberian pine forest, creating a monument to the Pythagorean theorem big enough to see from outer space.

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